a. Field of the Invention
The present invention relates to a process for producing decahydroacenaphthene, octahydroacenaphthene, hexahydroacenaphthene, tetrahydroacenaphthene, acenaphthene and mixtures thereof (designated as "acenaphthenes" in the following) by reacting cyclododecatriene (designated as CDT in the following) in the presence of a catalyst.
B. Description of the Prior Art
Various methods for producing acenaphthenes have been developed. For example, it has been known that acenaphthenes can be produced from CDT which is prepared by trimerization of butadiene. In this method, acidic catalysts such as Lewis acids, mineral acids or organic acids, or catalysts consisting of inert alumina or Kieselguhr retaining the above-described acids have been used as catalysts, and especially phosphoric acid is used widely.
However, phosphoric acid used as a component of the catalyst causes environmental pollution and thus it is necessary to recover phosphoric acid completely from these catalysts. Moreover, when acenaphthenes are prepared from CDT using these acidic catalysts, low polymerized substances produced as by-products accumulate during the process. In order to remove such a substance, a process of calcining the catalyst is required, but regeneration of these acidic catalysts is practically impossible.
Further, these acidic catalysts are corrosive and especially, catalysts consisting of strong acid must be handled very carefully.